Dave, this is good advice and a good place to start but I seem to remember an
interesting analysis Beezley did with an early version on MN many years ago. I
think he was using MN but I might be wrong. He did an analysis of the f/b and
gain of some HF yagi on a tower using the guy wire recommendations given in the
ARRL antenna book. The pattern and f/b were effectively altered in a negative
way. I think it might be a good idea to start with those recommendations but
to model the actual lengths to be sure.
73,
Gedas
e-mail w8bya@mchsi.com
online gallery http://gedas.cc
web page http://www.w8bya.com
----- Original Message -----
From: "Frederick M. Mott" <ab8ah@earthlink.net>
To: "'Dave'" <k4em@mindspring.com>; <towertalk@contesting.com>
Sent: Friday, December 23, 2005 10:03 AM
Subject: Re: [TowerTalk] guy wire resonance
Look in the ARRL Handbook, chapter 30 of the 2004 handbook has a table
called "Guy Wire Lengths to Avoid". I am sure this table can be found in
the older or newer versions of the ARRL Handbook. Fred
-----Original Message-----
From: towertalk-bounces@contesting.com
[mailto:towertalk-bounces@contesting.com] On Behalf Of Dave
Sent: Friday, December 23, 2005 8:17 AM
To: towertalk@contesting.com
Subject: [TowerTalk] guy wire resonance
I am replacing some guy wires on a 70' Rohn 25 with a 40m beam. What is the
spacing between the insulators so the guys are not resonant? The guys are
3/16" EHS and I am using the 500D insulators. I lost 3 guys due to ice storm
last week, the Phillystran was cut in half on the top 2 guys but the bottom
guy with all steel cable was undamaged. It was the 4000lb Phillystran.
Dave
_______________________________________________
See: http://www.mscomputer.com for "Self Supporting Towers", "Wireless
Weather Stations", and lot's more. Call Toll Free, 1-800-333-9041 with any
questions and ask for Sherman, W2FLA.
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_______________________________________________
See: http://www.mscomputer.com for "Self Supporting Towers", "Wireless Weather
Stations", and lot's more. Call Toll Free, 1-800-333-9041 with any questions
and ask for Sherman, W2FLA.
_______________________________________________
TowerTalk mailing list
TowerTalk@contesting.com
http://lists.contesting.com/mailman/listinfo/towertalk
_______________________________________________
See: http://www.mscomputer.com for "Self Supporting Towers", "Wireless Weather
Stations", and lot's more. Call Toll Free, 1-800-333-9041 with any questions
and ask for Sherman, W2FLA.
_______________________________________________
TowerTalk mailing list
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